*{
    margin: 0;
    padding: 0;
}

html body{
    width: 100%;
    height: 100%;
}

.wrap{
    width: 690px;
    height: 400px;
    margin: 100px;
    border: 1px solid red;
    position: relative;
    overflow: hidden;
}

.wrap img{
    width: 690px;
    height: 400px;
    display: block;
}

.wrap .tips{
    width: 690px;
    height: 400px;
    background: rgba(255, 0, 0, 0.5);
    position: absolute;
    left: 0px;
    top: 400px;
    text-align: center;
    font-size: 20px;
    color: blue;
    line-height: 400px;
    transition: all 0.5s;
}
.wrap:hover .tips {
    top: 0;
}